Stressors

Interactions between Climate Change and Other Stressors

Identified climate change impacts will likely be exacerbated by acting synergistically with other threats to biodiversity such as habitat loss and land-use change, introduced species and diseases, and altered water resources195.

Habitat loss and land-use change:

Increasing urbanization, farming and other land-use changes will potentially act as barriers to distributional shifts as species respond to the changing climate. Many species will be unable to cross modified habitats, potentially leaving them stranded in habitats that will increasingly become climatically unsuitable196.

Additionally, climate change will itself result in the loss of habitats in certain regions, such as montane areas and coastal fringes.

These interactions will increase extinction risk for many species, and potentially contribute to a more homogenized flora and fauna. Habitat restoration and increasing connectivity of habitats is key to reducing this risk, along with ensuring remaining habitats remain intact. More active interventionist methods such as assisted colonization may be a suitable strategy for a limited number of vulnerable species.197

Adaptation strategies in the face of these threats will include control and possible eradication of introduced species, tightening of quarantine and biosecurity measures, and education of landowners about introduced species and their impacts.

Water Extraction and pollutants:

As some regions of Australia become hotter and drier, the volume, quality, and seasonality of river flows will be affected, in turn affecting the ecological integrity of catchments and associated biodiversity, and exacerbating the existing conflicts between environmental and human needs. Any increase in water extraction, diversion and storage to increase water security for agriculture and urban areas will potentially have negative impacts on freshwater biodiversity207.

Ensuring adequate water resources for biodiversity, agriculture, and urban needs will require adaptation strategies such as using pipelines instead of open channels, adopting water efficient agricultural practices, recycling water, and pollution control. Restoration of riparian vegetation can potentially reduce bank erosion, as well as contributing to cooler water temperatures207.

Introduced species, pests and disease:

Climate change will likely interact with introduced species, including weeds and feral animals. Problem species such as buffel grass198, fire ants199, prickly acacia200and cane toads201, may expand their range, with implications for biodiversity. Introduced species that are not currently causing significant problems (such as so- called ‘sleeper’ weeds) may become problematic if climate change results in expanding populations202. However, the range of some pest species may decline, and management efforts should adapt accordingly.

Additionally, climate change may influence the prevalence and virulence of some diseases. Changes in climate and urban water storage practices may advantage some disease-carrying mosquitoes203. The distribution and impact of the amphibian chytrid fungus77and phytophthora (a fungus that causes die-back in plants), may be affected, and changing distributions of birds, bats, and rodents also have the potential to affect the distribution and spread of diseases204,205,206.

Adaptation strategies in the face of these threats will include control and possible eradication of introduced species, tightening of quarantine and biosecurity measures, and education of landowners about introduced species and their impacts.